- Level of measurement
- Structural equation model with latent variables
- Pragmatic
- Case-based
So, if your instructor get a score in 3 ~ 9, then you will know he is:
Method: statistically seeking for the "latent" variable.
\[ \begin{aligned} Democracy &\sim \beta_a\mbox{Competitiveness of political participation}; \\ Democracy &\sim \beta_b\mbox{Competitiveness of executive recruitment};\\ Democracy &\sim \beta_c\mbox{Openness of executive recruitment};\\ Democracy &\sim \beta_d\mbox{Constraints on the chief executive}. \end{aligned} \]
Sensible rather than puristical measurements.
"In spite of all their conceptual and observational differences, the various approaches yield highly similar classifications of regimes. Hence, there is no reason to think that the results that follow depend on the particular way regimes were classified" Przeworski et al. (2000, 55)